Single-blind, randomised, single centre, 2-way crossover pilot study to investigate the effectiveness of LAMELLEYE for the treatment of dry eye symptoms in patients with primary Sjögren's Syndrome.

The study is a 2-way crossover design comprising 2 treatments: the CE-marked LAMELLEYE dry eye drops, and a CE-marked comparator product. All Participants will be allocated to a treatment group in a random order.

The study design allows observations to be made between the treatments at both an intra- and inter-patient level regarding relationships between the patient's disease specific quality of life, symptoms and adverse events, and satisfaction with treatments.

Inclusion Criteria:

To be eligible for inclusion, each Participant must meet each of the following:

1. Male or female aged ≥ 18 years and ≤ 79 years at date of consent
2. Primary Sjögren's Syndrome diagnosed by a rheumatologist
3. Patient has symptoms of dry eye, and has failed to achieve symptom relief on adequate trial of standard topical therapy
4. Willing and able to attend Glasgow Caledonian University Vision Sciences Eye Clinic for therapy assessment; and to comply with all procedures and follow-up visits
5. Participant must have personally given written informed consent to allow anonymised data to be used in publications and presentations.

Exclusion Criteria:

Participants are excluded from the study if any of the following criteria are met:

1. Females who are pregnant, planning pregnancy or breastfeeding
2. Active ocular infection or current corneal ulceration
3. Ocular surgery within 6 months of study start date
4. Current contact lens wear
5. Any prior and/or current topical ophthalmic treatments that in the opinion of the CI or PI may interfere with the study outcomes
6. Started or changed the dose of chronic systemic medication known to affect tear production including, but not limited to antihistamines, anticholinergics, antidepressants, diuretics, corticosteroids or immunomodulators within 30 days prior to enrolment
7. Participants with known allergies to ingredients in any of the study treatments, or fluorescein
8. Participants who are judged inappropriate for inclusion in the study by the CI or PI.